Casting ingots



June 5, 1934.

CASTING INGOTS Filed Jan. 13, 1932 VINVENTOR? l A TTORNEYS.

A. R. RowE 1,961,529 V Patented June 5, 1934 CASTING INGOTS Andrew ReedRowe, Midland, Pa. Application January 13, 1932, Serial No. 586,439

3 Claims. (Cl. 22-139) 'I'his invention relates to improvements incasting steel ingots and other metal products.

One `of the objects ofthe invention is to furnish a device to be used incombination with a 5 mold and a hot-top, and in some cases in combination with an ingot mold, only to prevent the formation of blow holesor other imperfect spots in cast' metal'.

In the manufacture of iron and steel and other 1U metal products, greatdiflicultiesare encountered I in casting solid compact ingots, due tothe formation of these blow holes and -pipe, which are formed in theprocess of pouring, and during the period of solidification;

Blow holes or bubbles are mainly caused by trapped gases in the castmetal and it is known that such metal does not readily weld during therolling of the metal.

When the metal is poured in the mold, while the mold is cold, the metalfreezes against the mold, the ingot due to the difference internperature between the metal constituting the ingot and the moldshrinks away from the center of the ingot toward the sides of the mold.When freezes over quickly, the metal shrinking, toward the sides causesa snkhead or gas pockets, due to the metal freezing rapidly on the topof the ingot and not allowing the metal to feed down period ofsolidication.

The method of pouring ingots, most commonly used is, the metalisdischarged from a ladle, the ladle may contain as high as 125 tons ofmetal, the ladle nozzle usually being from one and one-half inch tothree inches in diameter through which the metal is poured into themold. Due to the quantity of melted metal in the ladle, it is evidentthat there is a heavy head pressure 0n the metal issuing from the ladlenozzle, and as the metal rises in the mold, this stream due to the headpressure, forces itself deep into the metal already poured into themold, and this causes slag and impurities to be forced deep into themetal, and the gases form blow holes or bubbles which are forced deepinto the metal and cannot rise to the surface readily until the streamfrom the ladle is shut off.

Some-of the bubbles or gases are forced too deepi'ntozthe metal to againrise to the surface, andthe-top freezing over quickly traps the gaseswithin the metal and prevents their escape.

The method and apparatus forming the subject matter of the presentinvention may be used with very little added expense over the common thepouring of the ingot is finished, the top to fill the shrinkagecavities, formed during the or ordinary method used in pouring metalsand without retarding production.

The invention will be described in detail in connection with theaccompanying drawing, in which: 50

Fig. 1 shows a detail sectional view of a mold and hot-top as ordinarilyused. It also shows what I denominate my Degasifier, In this figure thedegasier is shown on the bottom of the mold before starting to pour. l

Fig. 2 shows avview of the degasifier floated part way up the mold.

Fig. 3 shows the mold and hot-top filled with metal with the degasier,resting on the top of the metal.

Figs. 4, 5, 6 and 7 each show planand sectional Views of different typesof degasifiers, some with holes and others without.

A represents an ordinary mold, B a hot-top and C the molten metal pouredinto the mold A from` a ladle D.

The degasier E is preferably made of some refractory material, such aslire clay, or other insulating material, and the degasier may be round,square, oblong or of various shapes.

Referring to the operation of the degasiiier, the metal is poured fromthe ladle into the mold, but the stream is intercepted before reachingthe bottom of the mold, the surface of the degasier is convex on its topside and the stream of metal striking the degasier will follow theconvex contour of the degasifler without danger of splashing the mold.The degasier is designed to be slightly smaller than the insidedimensions of the hot-top, and the hot .top at its bottom end isbeveled, so that the degasiers convexed surface may easily pass thebottom end of the hot-top, in case the degasier floats up slightly offcenter.

The degasier by intercepting the stream of metal from the pouring nozzleof the ladle, and all during the pouring of the ingot, rests or rides ontop of the metal in the mold, prevents the stream of metal frompenetrating or forcing the i metal into the body of metal contained inthe mold and allowing the metal to follow the contour of the degasierwithout any penetrating yeffect upon the metal as it rises in the mold.

By intercepting the stream of metal from the ladle all during the llingof the mold and hottop, the stream of metal is broken up, thereby,separating various forms of gases and prevents the formation of blowholes in the metal.

The degasier is intended to be used in making what are known in thesteel art as killed steels and rimming or open steels and may be used incombination with a mold and a hot-top or in combination with a moldalone. It may be placed in the bottom of the mold before starting topour in the molten metal or may be dropped in the mold after starting topour in the metal.

The degasifer intercepts the stream of metal from the ladle and thusprevents the stream from striking the'bottom of the mold, thereby,eliminating the stream of metal from burning into the mold, causing theingot to be welded to themold,

thus eliminating the dangers of ingot or hanger cracks transverse orlongitudinal.`

From the foregoing, I believe that the operation and advantages of myso-called "Degasier may be readily appreciated by those skilled in theart, and I am aware that various changes may be made in the constructionillustrated and described, without departing from the spirit of theinvention as expressed in the following claims.

What I claim is:

, 1. An apparatus for molding metal comprising a mold, a device having aconvex upper surface and its perimeter conforming to the inner surfaceof the mold but smaller than said inner surface, said device beinglighter than the metal to be molded whereby when said device is placedin the mold and metal poured thereupon it will remain on the top ofthemetal as it rises in the mold and by reason of its convex top surfacewill cause the stream of poured metal to spread and run down its convexsurface to prevent the formation of bubbles in the metal.

2. An apparatus for molding metal comprising a mold, a device having aconvex top surface and a convex bottom surface, said device beingsmaller than the inner surface of the mold in any position it may occupyin the m'old and lighter than the molded metal, whereby as the metal ispoured into the mold said device will rise in the mold and rest on thetop of the molded metal to prevent the formation of bubbles in themetal.

3. An apparatus for molding metal comprising a mold, a hot top havingitslower end projecting into the mold, said lower end having an inwardlybevelled surface, a device having a convex top and ya convex bottomsurface, the perimeter of said device being smaller than either theinner surface of the mold or the inner surface of the hot top and saiddevice being lighter than the molded metal, whereby as the metal ispoured into the mold said devicewill rise in the mold and pass throughthe bevelled. opening in the hot top and rest on the top of the molded`metal at` the top of the. hot top to prevent the formation of bubblesinthe metal. i

ANDREW REED ROWE.

